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Object Identifiers are names assigned to things. Object Identifiers vary from abstract classes to actual items and from logical object to physical devices. All of these things and more are named. I think that the term "classes" needs some additional modifiers, e.g., classes of what? I also suggest that "actual items" is vague,. A more definitive terms is needed, but I am unclear on what we are trying to say here to make a suggestion The things that are named can include logical or physical objects, and names can be given either to types of things or to the things themselves. We can call the first a class identifier, since it refers to a class (or type, or category) of things; the latter an instance identifier. These terms come from computer programming, there may be other terms from ontology or elsewhere that are more suitable. In the case of an automobile, the VIN is the instance identifier, while the make and model would be class identifiers.
On Object Identifiers vs ITU-T OIDs
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